// Copyright 2006-2008 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

// Used for building with external snapshots.

#include "src/snapshot/snapshot.h"

#include "src/base/platform/mutex.h"
#include "src/snapshot/snapshot-source-sink.h"
#include "src/v8.h" // for V8::Initialize

#ifndef V8_USE_EXTERNAL_STARTUP_DATA
#error snapshot-external.cc is used only for the external snapshot build.
#endif // V8_USE_EXTERNAL_STARTUP_DATA

namespace v8 {
namespace internal {

    static base::LazyMutex external_startup_data_mutex = LAZY_MUTEX_INITIALIZER;
    static v8::StartupData external_startup_blob = { nullptr, 0 };

    void SetSnapshotFromFile(StartupData* snapshot_blob)
    {
        base::MutexGuard lock_guard(external_startup_data_mutex.Pointer());
        DCHECK(snapshot_blob);
        DCHECK(snapshot_blob->data);
        DCHECK_GT(snapshot_blob->raw_size, 0);
        DCHECK(!external_startup_blob.data);
        DCHECK(Snapshot::SnapshotIsValid(snapshot_blob));
        external_startup_blob = *snapshot_blob;
    }

    const v8::StartupData* Snapshot::DefaultSnapshotBlob()
    {
        base::MutexGuard lock_guard(external_startup_data_mutex.Pointer());
        return &external_startup_blob;
    }
} // namespace internal
} // namespace v8
